SIDS may result from altered neuromuscular events related to the laryngeal closure reflex. Firstly, we have proposed to study the effects of pharyuno-laryngeal afferent stimulation of phrenic and thyroartytenoideus discharge patterns in response to various levels of anesthesia, airway resistance, pO2, and pCO2. Secondly, if altered reflex events can be demonstrated, then their possible causes will be investigated in terms of age dependent naso-oral breathing patterns as they would affect such variations in ventilatory resistance, pO2, and pCO2. It is hoped that such an investigation of SIDS may provide basic insight into our general understanding of postnatal respiratory development.